Textbook-Integrated Guide to Educational Resources

TIGER

Imidazole as a pH Probe: An NMR Experiment for the General Chemistry LaboratoryWilliam J. Hagan, Jr., Dennis L. Edie, and Linda B. CooleyAn experiment is described that employs the 1H-NMR signal of aqueous imidazole to determine the pH of an unknown solution. The procedure involves the preparation of a calibration curve, which is then used for the analysis of the unknown(s).Hagan, William J., Jr.; Edie, Dennis L.; Cooley, Linda B. J. Chem. Educ.2007, 84, 1188.

Acids / Bases |

Aqueous Solution Chemistry |

Aromatic Compounds |

Calibration |

NMR Spectroscopy |

pH

pH Paradoxes: Demonstrating That It Is Not True That pH ≡ -log[H+]Christopher G. McCarty and Ed VitzSix demonstrations highlighting paradoxes that arise if pH is incorrectly defined as -log[H+] are presented as justification for the recommendation that pH should be correctly defined as pH = -log aH+ in textbooks.McCarty, Christopher G.; Vitz, Ed. J. Chem. Educ.2006, 83, 752.

Teaching pH Measurements with a Student-Assembled Combination Quinhydrone ElectrodeFritz Scholz, Tim Steinhardt, Heike Kahlert, Jens R. Pörksen, and Jürgen BehnertA combination pH electrode that can be assembled by the student is described. It consists of a glass holder and two sensors in the form of rubber stoppers that contain quinhydrone and graphite. The combination electrode is suitable to teach potentiometric measurements, pH measurements, and the interplay of acidbase and redox equilibria. The electrode meets highest safety standards and overcomes the troubles associated with the use of the conventional quinhydrone electrode.Scholz, Fritz; Steinhardt, Tim; Kahlert, Heike; Pörksen, Jens R.; Behnert, Jürgen. J. Chem. Educ.2005, 82, 782.

The pH of any mixture of monoprotic acids and basesHerman, D. P.; Booth, K. K.; Parker, O. J.; Breneman, G. L.115. Bits and pieces, 44. The pH of any mixture of monoprotic weak and strong acids and bases can be calculated. A curve can also be plotted for the titration of the mixture by any monoportic weak or strong acid or base.Herman, D. P.; Booth, K. K.; Parker, O. J.; Breneman, G. L. J. Chem. Educ.1990, 67, 501.

Acids / Bases |

Titration / Volumetric Analysis |

pH

pH measurements on the overhead projectorSolomon, Sally; High, NancyUniversal indicator solution and a corresponding pH indicator chart are used to make pH measurements of an overhead projector where the results are visible to all students in a large lecture hall.Solomon, Sally; High, Nancy J. Chem. Educ.1987, 64, 964.

pH |

Acids / Bases |

Dyes / Pigments

Buffer capacity: An undergraduate laboratory experimentRusso, Steven O.; Hanania, George I. H.A quantitative experiment that can demonstrate buffer action and the measurement of buffer capacity, for a given buffer system, over a range of pH.Russo, Steven O.; Hanania, George I. H. J. Chem. Educ.1987, 64, 817.

Acids / Bases |

pH |

Aqueous Solution Chemistry

Density gradient columns for chemical displaysGuenther, William B.An important advantage of these demonstrations of complex chemistry is that students can observe them over a period of time as they grasp concepts of solution equilibria.Guenther, William B. J. Chem. Educ.1986, 63, 148.

Acids / Bases |

pH |

Coordination Compounds |

Metals

An invitation to experiment with an experimentPhanstiel, OttoStudents are asked to develop an experiment in which they isolate an acid / base indicator from a flower and determine the pH at which it changes color.Phanstiel, Otto J. Chem. Educ.1985, 62, 522.

Buffer effect demonstration on the overhead projectorHobe, Paul G., Jr.Illustrates that one drop of dilute acid or base will change the pH of water by a large amount while larger amounts can be added to a buffer solution before any change is noted.Hobe, Paul G., Jr. J. Chem. Educ.1979, 56, 47.

Emphasis on acids and basesJ. Chem. Educ. StaffConsiders the acidity or basicity in soils and natural waters; the acid-base balance in body chemistry; acidic and basic foods; the approximate pH values of common fluids; examples of acidic, basic, and neutral drugs; and the commercial preparation of nitric acid.J. Chem. Educ. Staff J. Chem. Educ.1977, 54, 626.

Acids / Bases |

Water / Water Chemistry |

Food Science |

Applications of Chemistry |

pH |

Drugs / Pharmaceuticals

Effect of Ionic Strength on Equilibrium ConstantsSeymour, M. D.; Fernando, QuintusInvolves the determination of the acid dissociation constant of bromcresol green by a spectrophotometric method; using a graphing calculator, each student can perform the laboratory work and obtain his own data set.Seymour, M. D.; Fernando, Quintus J. Chem. Educ.1977, 54, 225.

A new buffer demonstrationFriedman, NormanAn Alka-Seltzer tablet in water is used as a buffer system and its resistance to changes in pH are compared to solutions of buffered aspirin and aspirin.Friedman, Norman J. Chem. Educ.1975, 52, 605.

Easily prepared wide range buffer seriesCarmody, Walter R.A series of buffers with pH values ranging from 2.0 to 12.0 that requires the preparation of only two stock solutions and requires only three common chemicals.Carmody, Walter R. J. Chem. Educ.1961, 38, 559.

Research project for general chemistry laboratorySchwolow, JeanIn order to modify the routine experiment in which students know the answers before ever entering the laboratory, freshmen were presented with a simulated research project connected with acids, bases, and pH measurements.Schwolow, Jean J. Chem. Educ.1958, 35, 416.

Undergraduate Research |

Acids / Bases |

pH |

Aqueous Solution Chemistry

Amphoteric molecules, ions and saltsDavidson, DavidIt is the aim of this paper to call attention to the splendid opportunity amphoteric substances afford for the teaching of acid-base principles.Davidson, David J. Chem. Educ.1955, 32, 550.